UVA11981 Corrupted Friendship

Description

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=229&page=show_problem&problem=3132 [PDF](https://uva.onlinejudge.org/external/119/p11981.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11981/b1ad94d6e8dc4f4a8e695be7a04c5ebcd646ea1c.png)

Input Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11981/2e4544e16c2fbbb75ec53a39ae8042cb2efcd8e2.png)

Output Format

![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA11981/66d3a8e924f0efa225b2e3a3c28d8015b5cdb23f.png)